In addition to supporting point-to-point connections, contemporary communication systems generally also support conference circuits, i.e., connections between three or more subscribers. Conference circuits can be set up, for example, between terminal devices for voice, video, or multimedia communication or between personal computers.
As part of a development currently taking place, communication connections and in particular real-time connections are increasingly also being carried over packet-oriented communication networks like, for example, local area networks or wide area networks such as, e.g., the Internet. Internet telephony, which is frequently also referred to as Voice/Video over Internet Protocol (VoIP) telephony is based on this technology, for example.
In the migration of circuit-oriented communication systems to packet-oriented communication systems such as, e.g., VoIP systems, manufacturers of circuit-oriented switching equipment, private branch exchange (PBX) equipment as it is known, have a major interest in continuing to use existing circuit-oriented conference equipment and conference software. Consequently, traditional circuit-oriented switching equipment, supplemented with packet-oriented interfaces and packet-oriented transport protocols, is frequently used in packet-oriented communication networks. This type of upgraded switching equipment is frequently also referred to as IP-PBX.
Previously, when circuit-oriented conference equipment was used in packet-oriented communication networks, the user-data packets were mainly processed by traditional, circuit-oriented processing resources such as, e.g., a Time Division Multiplex (TDM) switching unit or a conference bridge, in order in this way to mix different user-data streams, for example.
However, this type of user-data processing frequently necessitates multiple transitions between packet switching (VoIP) and circuit switching (TDM), as a result of which voice quality, for example, is substantially impaired. Furthermore, there is in this case a heavy dependency on existing circuit-oriented conference hardware, rendering migration to a native Internet Protocol-based system very difficult.